Fix error in FastClassVerifier (AnalyzerException with immediate return of ternary operator with generic return type)

Author: vsilaev

net.tascalate.javaflow.providers.asm3/src/main/java/org/apache/commons/javaflow/providers/asm3/FastClassVerifier.java

@@ -32,7 +32,7 @@ public Value copyOperation(final AbstractInsnNode insn, Value value) throws Anal
     @Override
     public Value unaryOperation(final AbstractInsnNode insn, Value value) throws AnalyzerException {
         // Fix error with analyzer for try-with-resources (it sees uninitialized values)
-        if (insn.getOpcode() == Opcodes.ALOAD && (value instanceof BasicValue && !((BasicValue)value).isReference())) {
+        if (insn.getOpcode() == Opcodes.ARETURN && (value instanceof BasicValue && !((BasicValue)value).isReference())) {
             value = newValue(Type.getType("Lnull;"));
         }
         return super.unaryOperation(insn, value);    
@@ -81,13 +81,9 @@ protected boolean isSubTypeOf(final Value value, final Value expected) {
                 return type.equals(expectedType);
             case Type.ARRAY:
             case Type.OBJECT:
-                if ("Lnull;".equals(type.getDescriptor())) {
-                    return true;
-                } else {
-                    // We are transforming valid bytecode to (hopefully) valid bytecode
-                    // hence pairs of "value" and "expected" must be compatible
-                    return true;//isAssignableFrom(expectedType, type);
-                }
+                // We are transforming valid bytecode to (hopefully) valid bytecode
+                // hence pairs of "value" and "expected" must be compatible
+                return true;//isAssignableFrom(expectedType, type);
             default:
                 throw new Error("Internal error");
         }

net.tascalate.javaflow.providers.asm4/src/main/java/org/apache/commons/javaflow/providers/asm4/FastClassVerifier.java

@@ -27,6 +27,15 @@ public BasicValue copyOperation(final AbstractInsnNode insn, BasicValue value) t
         }
         return super.copyOperation(insn, value);
     }
+    
+    @Override
+    public BasicValue unaryOperation(final AbstractInsnNode insn, BasicValue value) throws AnalyzerException {
+        // Fix error with analyzer for try-with-resources (it sees uninitialized values)
+        if ((insn.getOpcode() == Opcodes.ARETURN) && !value.isReference()) {
+        	value = newValue(Type.getType("Lnull;"));
+        }
+       	return super.unaryOperation(insn, value);
+    } 
 
     @Override
     public BasicValue newValue(final Type type) {
@@ -67,13 +76,9 @@ protected boolean isSubTypeOf(final BasicValue value, final BasicValue expected)
                 return type.equals(expectedType);
             case Type.ARRAY:
             case Type.OBJECT:
-                if ("Lnull;".equals(type.getDescriptor())) {
-                    return true;
-                } else {
-                    // We are transforming valid bytecode to (hopefully) valid bytecode
-                    // hence pairs of "value" and "expected" must be compatible
-                    return true;//isAssignableFrom(expectedType, type);
-                }
+                // We are transforming valid bytecode to (hopefully) valid bytecode
+                // hence pairs of "value" and "expected" must be compatible
+                return true;//isAssignableFrom(expectedType, type);
             default:
                 throw new Error("Internal error");
         }

net.tascalate.javaflow.providers.asm5/src/main/java/org/apache/commons/javaflow/providers/asm5/FastClassVerifier.java

@@ -28,6 +28,16 @@ public BasicValue copyOperation(final AbstractInsnNode insn, BasicValue value) t
         return super.copyOperation(insn, value);
     }
 
+    @Override
+    public BasicValue unaryOperation(final AbstractInsnNode insn, BasicValue value) throws AnalyzerException {
+        // Fix error with analyzer for try-with-resources (it sees uninitialized values)
+        if ((insn.getOpcode() == Opcodes.ARETURN) && !value.isReference()) {
+        	value = newValue(Type.getType("Lnull;"));
+        }
+       	return super.unaryOperation(insn, value);
+    }  
+
+
     @Override
     public BasicValue newValue(final Type type) {
         if (type == null) {
@@ -67,13 +77,9 @@ protected boolean isSubTypeOf(final BasicValue value, final BasicValue expected)
                 return type.equals(expectedType);
             case Type.ARRAY:
             case Type.OBJECT:
-                if ("Lnull;".equals(type.getDescriptor())) {
-                    return true;
-                } else {
-                    // We are transforming valid bytecode to (hopefully) valid bytecode
-                    // hence pairs of "value" and "expected" must be compatible
-                    return true;//isAssignableFrom(expectedType, type);
-                }
+                // We are transforming valid bytecode to (hopefully) valid bytecode
+                // hence pairs of "value" and "expected" must be compatible
+                return true;//isAssignableFrom(expectedType, type);
             default:
                 throw new Error("Internal error");
         }